3/20/2006

Centre Daily Times (State College, PA)

Many people think organic farming will produce food that is healthier and better for the environment than that produced with non-organic methods. Organic sales are increasing at 20 percent per year, and policymakers are directing taxpayer money toward organic. For example, Sen. Hillary Clinton, D-N.Y., recently announced a program to help dairy farmers in her state transition to organic, and Norway set a goal to get 10 percent of the managed area to be organic by 2009. With this interest in organic food production, it is important to realize that some claims of organic food remain elusive whereas serious challenges are often ignored. First, there is no consensus about health claims of organic food. According to the United Nations' Food and Agriculture Organization, studies have shown no clear, consistent results. According to the USDA, the organic label does not mean that organic food is superior, safer or healthier than conventional food. We are blessed with a very safe food supply, although, admittedly, many of us eat unhealthily. The latter is not because of non-organic food, but because we eat too much fat, sugar and carbohydrates, and too few vegetables and fruits.

Second, organic farming has some serious environmental challenges.

Organic producers use intensive tillage for soil preparation and weed control. Plowing favors runoff and erosion. It oxidizes soil organic matter and destroys soil aggregates. Tillage is also harmful to many soil organisms such as earthworms. No-till systems have been developed where soil is protected by a mulch, reducing erosion and runoff. This increasingly popular practice is now used on 23 percent of U.S. cropland.

Living vegetation is killed with an herbicide and crops are planted directly into a mulch with a no-till planter. Soil organic matter is preserved, surface aggregation is improved, and soil organisms such as earthworms are favored. Without herbicides, continuous no-till farming is virtually impossible. Organic farmers rely primarily on compost, animal manure or green manure crops to supply soil fertility. The nutrients in these organic sources typically do not match crop demands. So it is easy to over-apply nutrients such as phosphorus, while nitrogen needs are just barely met. When cover crops or manure are plowed down, nitrogen can be released rapidly. Unfortunately, no crop is present to take these nutrients up immediately. Hence the potential for significant nutrient losses in organic farming. Commercial fertilizer could help complement organic sources of fertility, reducing the opportunity for losses to the environment, but these products are not allowed in organic production. The third and greatest challenge for organic farming is, however, how to produce enough affordable food without sacrificing natural ecosystems. The world population has doubled since 1960, now exceeding 6 billion, and is expected to reach 9 billion in 2050. Despite fears in the 1970s of widespread famines, the average world citizen (even in developing countries) eats more now than in the 1960s. According to the FAO, food production outpaced population growth and the price of food decreased 40 percent in real terms between 1960 and 1999. Seventy-eight percent of the increase in food production was due to increased production per acre of land made possible by the use of improved crop varieties, chemical fertilizers, crop protectants and improved machinery. Although competitive yields are possible with organic production, a major proportion of the world's lands would have to be devoted to green manure crops to fix nitrogen. Expansion of cropland comes at the expense of natural habitat and is sometimes impossible. Recently, members of the Chinese Academy of Sciences expressed their concern about an organic food strategy for China.

They pointed out that China produces enough food for 21 percent of the world population on 9 percent of the world's cultivated land. This has only been possible because 75 percent of crop nutrients are now supplied by chemical fertilizer, compared with only 22 percent in 1965. If China were to adopt organic practices on a large scale, cropland would have to be expanded, which is no option in land-scarce China. Health promises of organic food remain elusive, whereas it has significant environmental challenges, including its reliance on intensive tillage and organic nutrient sources. The need to expand cropland means less natural habitat, and rising food costs present a problem for the world's urban poor. These issues need to be seriously considered before we become too enamored with organic.

Sjoerd W. Duiker is an assistant professor of soil management at Penn State. The opinion of the columnist does not necessarily reflect the viewpoint of the university.